1. Field of the Invention
The present invention relates to a manual locking assembly for a quick connect coupling.
Quick connect couplings of this kind are used, inter alia, for connecting a wireline to a tool string.
2. Description of the Related Art
The following patents describe prior art:
FR 928 506;
U.S. Pat. No. 5,052,849; and
U.S. Pat. No. 5,607,250.
These patents disclose quick connect couplings based on a male part having radial sidewalls that are brought into corresponding engagement in radial grooves of a female part and locked therein by various locking plates in order to resist high torsional forces in addition to tensile forces. The coupling of the male and female parts also occurs laterally, with the interlocking being accomplished by means of a cylindrical spring loaded latching element, suspended in the female part, that is guided axially down in the top of the male part and locked. Normally, unlocking is accomplished using a special tool and a pipe wrench.
EP 1229211 discloses a manual quick connect coupling for a wireline tool comprising a male part having a number of retaining lugs and a transversal groove provided at the front end of the male part. The arrangement also comprises a female part, a connector part, a spring, and a sleeve-shaped part to be mounted in the female part.
U.S. Pat. No. 4,986,690 relates to a quick connect coupling wherein it is known that a male pin is guided into a locking sleeve and brought into contact with a locking assembly. The male pin is then rotated to bring guiding and retaining lugs into abutment in corresponding locking grooves. Simultaneously, the locking assembly is brought into engagement with a groove cut at the tip of the male pin, whereby a spring is unloaded. The publication further shows how uncoupling is accomplished by compressing the spring and bringing the male pin to the release position by rotation. This is accomplished using special tools and a pipe wrench.
U.S. Pat. No. 4,655,631 and U.S. Pat. No. 4,784,543 describe lockable quick connect couplings wherein the coupling is achieved by guiding the male pin into a locking sleeve. It is further shown that a number of guiding and retaining lugs extend from the outer radius of the male pin and that the male pin is retained by rotation, so that the retaining lugs are brought into abutment in locking grooves in the locking sleeve.